nav ul li:nth-child(4) a {
  color: #c5842d;
  border-bottom: 2px solid #fff;
}

/* banner------------------------------------------- */
.banner {
  width: 100%;
  height: 24rem;
  background-color: black;
  position: relative;
}

.banner .img {
  width: 100%;
  height: 99.8%;
  display: block;
}

.banner .banner-content {
  position: absolute;
  top: -1.25rem;
  right: 3.35rem;
  width: 19.65rem;
  text-align: left;
}

.banner .banner-content .one {
  font-family: 'heiti';
  font-size: 1.4rem;
  line-height: 1.95rem;
  margin-top: 10.25rem;
  text-align: center;
}

.banner .banner-content .one a {
  color: #fff;
}

/* banner_center-------------------------------------------- */
.banner_center {
  width: 100%;
  height: 45rem;
  padding-top: 1.55rem;
  padding-bottom: 2rem;
}

.banner_center .nav-content {
  position: relative;
  top: 1em;
  left: 6.35em;
  width: 46.6rem;
  text-align: left;
}

.banner_center .nav-content .one {
  font-size: 0.4rem;
  color: black;
  line-height: 1.35rem;
  margin-top: -1.45rem;
  width: 18.45rem;
}

.banner_center .content_top{
  width: 80%;
  height: 7.25rem;
  /* border: 1px solid red; */
  margin: 0 auto;
  margin-top: 3.25rem;
  text-align: center;
}
.banner_center .content_top .top_one{
  font-family: 'heiti';
  font-size: 2.10rem;
  color: #404040;
}

.banner_center .big_box{
  width: 80%;
  height: 35.25rem;
  /* border: 1px solid red; */
  margin: 0 auto;
}

.banner_center .big_box .content_left{
  width: 56%;
  height: 99.8%;
  /* border: 1px solid red; */
  float: left;
  margin-right: 6%;
}
.banner_center .big_box .content_left p{
  font-size: 0.95rem;
  line-height: 1.55rem;
}
.banner_center .big_box .content_left img{
  float: right;
}
.banner_center .big_box .content_right{
  width: 37%;
  height: 99.8%;
  /* border: 1px solid red; */
  float: left;
}
.banner_center .big_box .content_right img{
  width: 100%;
  height: 35%;
  margin-top: 1.25rem;
}
.banner_center .big_box .content_right img:hover {
  background-color: #fff;
  box-shadow: 0 0 7px 3px #5328f0;
}







/* banner-bottom-------------------------------------------- */
.banner-bottom {
  width: 100%;
  padding-top: 1.55rem;
  padding-bottom: 2rem;
}

.banner-bottom .return-top {
  text-align: center;
}
.banner-bottom .return-top a{
  font-size: 0.65rem;
  color: black;
}
.banner-bottom .return-top .up{
  position: relative;
  left: -32%;
}
.banner-bottom .return-top .down{
  position: relative;
  left: 31%;
}
.banner-bottom .return-top button {
  width: 3.75rem;
  height: 1.45rem;
  background-color: #9c9c9c;
  margin-bottom: 1.25rem;
  position: relative;
  top: 0.25rem;
}

.banner-bottom .return-top button a {
  color: #fff;
  font-size: 0.15rem;
}

.clear {
  width: 100%;
  padding-top: 1px;
}